Level.



- 6.1. MAIIsIi-N.

LEVEL.

APPLICATION FILED SEPT. I8, 19u.

1,265,468. Patent-ed May?, 1918.

INVENTOR WITNESSES:

A'xvrons mrs 'narran srnans errance ernten CHRESTEN TORBEN MADSEN, OF OAKLAND, CALIFORNIA.

' LEVEL.

Application filed September 18, 1917.

To all Aui/0m t may concern.'

Be it known that l, CHnns'rnN T. MADSEN, a citizen of the United States, residing at (lakland. in the county of Alameda and State of California, 1nave invented new and useful Improvements in Levels, of which the following is a specification.

This invention relates to levels in which pendulums are used instead of spirit tubes; and has for its object to simplify and improve the construction and operation of levels of this type.

ln carrying out the invention a stock or frame of suitable length and cross-section is fitted with a plurality of sensitively mounted pendulums, preferably three in number. One of these is centrally mounted in the stock to indicate horizontal lines, while the others are mounted near the ends of the stock to indicate perpendicular lines.

One form of level embodying` the invention is exemplified in the following description and illustrated in the accompanying drawings, in which- Figure 1 is a plan view of the level.

Fig. 2 is a cross sectional view on the line 2-2 of Fig. 1.

Fig. 3 is a similar view on line 3-3 of Fig. 1.

In constructing the level, a frame or stock A., of suitable dimensions., is formed with chambers, in which are mounted pendulums B, C and D. The number and arrangement of these chambers and pendulums could, of course, be varied to suit different purposes, but in the preferred arrangement a pendulum C is centrally mount-ed in the stock to indicate horizontal lines, while the two longer pendulums B and D are mounted near the ends of the stock, preferably hanging in the same direction, to indicate vertical lines.

All the pendulums used being essentially similar, repetition in the description will be avoided by describing the construction and operation of only one of them. Taking pendulum C as an example, it will be seen, by referring to Fig. 3, that it consists of a rod 10, having a weight l1 at its lower end and a spherical supporting member l2 at its upper end. The member 12 is supported Specification of Letters Patent.

Patented May 1918.

Serial No. 192,011.

upon ball-bearings 13, carried by a cup 14, mounted near the upper end of the chamber in the stock A. The pendulum C is thus suspended upon an antifriction bearing which permits the greatest possible freedom of motion, the pendulum being able to rotate on its vertical axis or swing in any plane.

To facilitate reading, however, it is necessary to confine the swinging motion of the pendulum to a plane parallel to the sides of the stock A. This is accomplished by means of a roller 15 journaled on the rod 10 just above the weight 11 to contact with one or the other of guides 16, carried by side plates 17. The guides 16 are sufficiently spaced apart so that roller 15 can only engage one of them at a time. If for any reason the roller 15 should become obstructed and fail to rotate upon its axis, ant-ifriction guiding means would still be in operation, because then the pendulum a whole would rotate upon its ball-bearing support and the roller 15 would roll against the guide 16 liust as it would if rotating upon its own axis.

Practically infallible antifric'tion means are thus provided to confine the swinging of the pendulum to approximately a single plane, so that by looking through windows 18, formed in the plates 1.7, consistently accurate readings may be taken. To assist in making accurate indications conical pointer 19 is formed on the lower side of the weight 11, the apex of the pointer coinciding with the axial line of the pendulum. ludicators 20 are formed in the plates 17 on the lower sides of the windows 18 at properly fixed points, so that by coincidence of the pointers 19 and the indicators 20, it can accurately be determined when the pointers 19 are in such a position that a horizontal line ifs-indicated.

Having thus described my invention, what I claim and vdesire to secure by Letters Patent is- 1. A level consisting of a chambered stock, a pendulum rod having a weight at its lower end, a ball bearing at its upper end, guides upon each side of the rod, and a roller journaled upon the rod and adapted to travel between the guides.

2. In a level of the character described, a

titl

pendulum rod with anti-frictional bearings In testimony whereof I have hereunto set at the upper end, a guide roller journaled my hand in the presence of two subscribing upon the rod and a weight atthe lower end witnesses. v

of the rod and having a spur inline with the CHRESTEN TORBEN MADSEN. rod., and a coacting indicating means with Witnesses:

which the spur coincides when a Level is JOHN H. HERRING,

obtained. W. W; HEALEY.

Copies of this patent may be obtained for ve cents each, by addressing the Commissioner of Patents, Washington, D. C. 

